Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Laser light speckle is a pattern that is observable when a coherent light source interacts with a surface and/or a scattering transmission medium, such as air or an optical fiber. For example, the effect can be observed when a visible laser pointer interacts with a projector screen. Speckle occurs due to optical interference between relative optical phases arriving at a detector by traveling over a distribution of distances. As such, interactions between a laser beam and a diffusive surface (e.g., paper or white paint) may result in observable speckle patterns.